Simplify the expression. $(-4a^{4}-4a^{3}+3a)(-6a^{4})$
Solution: First use the distributive property. $ - 4 a^4 (-6 a^4) - 4 a^3 (-6 a^4) + 3 a (-6 a^4) $ Simplify. $24a^{8}+24a^{7}-18a^{5}$